Electronic apparatuses, such as digital cameras and mobile phones, in which image display devices, such as liquid crystal panels and organic EL panels, are mounted have been used. In recent years, portable electronic apparatuses, such as smart phone terminals and tablet terminals, which display relatively large images and include input devices, such as touch panels, have rapidly come into widespread use. PTL 1, for example, discloses a technology related to such a smart phone. In a portable electronic apparatus, a light-transmissive cover plate for protecting an image display surface of an image display device, such as a liquid crystal panel or an organic EL panel, is disposed on a portion of a housing of the electronic apparatus. The light-transmissive cover plate is composed mainly of strengthened glass made of, for example, aminosilicate glass. In smart phone terminals and tablet terminals, with the increase in the resolution of displayed images, communication speed, and software functionality, the amount of information processed by information processing devices, such as a central processing unit (CPU), has increased. Accordingly, there is a need to reduce the information processing time, that is, to increase the information processing speed.